The ubuntustudio dkms hook is only created when we're building ubuntustudio, so only chmod it when it exists. LP: #1983521.

debian/changelog

@@ -1,3 +1,10 @@
+livecd-rootfs (2.765.10) UNRELEASED; urgency=medium
+
+  * The ubuntustudio dkms hook is only created when we're building
+    ubuntustudio, so only chmod it when it exists.  LP: #1983521.
+
+ -- Steve Langasek <steve.langasek@ubuntu.com>  Thu, 04 Aug 2022 12:10:37 -0700
+
 livecd-rootfs (2.765.9) jammy; urgency=medium
 
   * When adding the new RISC-V platforms, some of the generic non-SUBARCH code

live-build/auto/config

@@ -1306,8 +1306,8 @@ env DEBIAN_FRONTEND=noninteractive \
        apt-get -y autoremove --purge v4l2loopback-dkms v4l2loopback-utils
 
 EOF
+	chmod +x config/hooks/100-ubuntustudio-dkms.chroot
 fi
-chmod +x config/hooks/100-ubuntustudio-dkms.chroot
 
 if $BINARY_REMOVE_LINUX; then
 	cat > config/binary_rootfs/excludes << EOF